The present invention relates to a simplified and inexpensive approach to asceptically filling containers.
There are two generally accepted approaches to packaging sterile media in containers. The first and simplest involves filling a non-sterile container with a non-sterile medium and then autoclaving the filled container. The approach is only suitable where the filling medium is heat stable and the container can withstand the heat and pressures involved. The second approach is used where the filling medium is heat labile and/or the container cannot withstand autoclaving. Under such circumstances the container can be pre-sterilized chemically and the filling medium can be sterile filtered into the container under clean room conditions. It is this latter approach with which the present invention is concerned. More specifically, it is an object of the present invention to provide a method and apparatus for asceptically filling pre-sterilized containers without requiring clean room conditions.
There are commercially available a variety of clean work station units in which asceptic filling can be effected. Such units provide work stations through which filtered air is forced to flow in laminar state and at sufficient velocity through the station to prevent contaminated outside air from entering the work platform area. These stations are widely used but suffer from the disadvantages of high cost, virtual immobility, and a limited storage and work area. It is therefore another object of the present invention to provide a method and apparatus for filling pre-sterilized containers which is inexpensive, portable and permits virtually unlimited storage and work area. It is a more specific object of the present invention to provide an efficient method and apparatus for asceptically filling pre-sterilized containers in an ambient environment which does not require sterilization, the maintenance of clean room conditions, or a clean work station.
There is also commercially available an asceptic filling funnel which permits sterile filling media to displace sterile gas previously placed in the container. As the gas is displaced it is directed to provide a protective shield around the container, thereby keeping contaminants out of the container. However, after the container has been filled the shield provided by the sterile gas is dissipated, an abrupt pressure differential is often created which tends to suck in surrounding air. If the funnel is used in a clean work station the surrounding air causes little contamination; in a general work area, however, the result is a high incidence of contamination.
It is therefore a further object of the present invention to provide a method and portable apparatus for asceptically filling pre-sterilized containers in an untreated environment.